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Junfeng Fan - One of the best experts on this subject based on the ideXlab platform.
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Changes in the Radical Scavenging Activity of Bacterial-Type Douchi, a Traditional Fermented Soybean Product, during the Primary Fermentation Process
Bioscience biotechnology and biochemistry, 2009Co-Authors: Junfeng Fan, Masayoshi Saito, Yanyan Zhang, Xiaojie Chang, Li ZaiguiAbstract:We studied the effects of isoflavones and peptides on antioxidant activities of bacterial-type Douchi during fermentation. Radical scavenging activities increased with increasing fermentation time. Isoflavone conversion was not obvious, while soy protein hydrolyzed dramatically during fermentation. These results suggest that soybean peptides rather than isoflavones result in variations in antioxidant activity in bacterial-type Douchi.
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comparison of angiotensin i converting enzyme inhibitor activities of pre fermented Douchi a chinese traditional fermented soybean food started with various cultures
International Journal of Food Engineering, 2009Co-Authors: Lijun Yin, Yongqiang Cheng, Kohji Yamaki, Junfeng FanAbstract:Pre-fermented Douchi, also called Douchi qu, is a salt-free semi-product of a Chinese traditional fermented soybean food (Douchi), which is classified into three types, that is, Aspergillus-type, Mucor-type and Bacteria-type. In this work, angiotensin I-converting enzyme (ACE) inhibitor activities of Douchi qu started by different types of cultures were compared. It was found that Douchi qu fermented with Aspergillus oryzae, Mucor wutungkiao, Bacillus subtilis natto and Bacillus subtilis B1 showed significantly different (p < 0.05) ACE inhibitor activities with decreasing IC50 values of 0.4991, 0.3535, 0.2294 and 0.0901 mg/mL, respectively. Twenty-five fractions were separated by gel filtration chromatography and the strongest ACE inhibitor activity was observed in a fraction with high contents of glycine, lysine and arginine from B. subtilis B1 fermented sample. Results indicated that the type of starter cultures affected significantly the production of ACE inhibitors in Douchi qu, and that B. subtilis B1 could be potential candidate as an inoculant to prepare fermented soybeans with strong ACE inhibitor activity in functional food industry.
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Isolation and characterisation of a novel angiotensin I-converting enzyme-inhibitory peptide derived from Douchi, a traditional Chinese fermented soybean food
Journal of the Science of Food and Agriculture, 2009Co-Authors: Junfeng Fan, Szesze Tan, Yanyan Zhang, Eizo TatsumiAbstract:BACKGROUND:Douchi, a traditional fermented soybean food, has recently attracted a great deal of attention owing to its superior physiological activity. In the present study the angiotensin I-converting enzyme (ACE)-inhibitory activity of typical Douchi procured from various regions of China was analysed. An ACE-inhibitory peptide derived from the most potent Douchi was also isolated and characterised. The pattern of ACE inhibition and resistance to hydrolysis by gastrointestinal proteases of this peptide are described. RESULTS: ACE-inhibitory activities were detected in all Douchi samples, with IC50 values ranging from 0.204 to 2.011 mg mL−1. Among the Douchi samples, a Mucor-type Douchi exhibited the most potent ACE-inhibitory activity (IC50 = 0.204 mg mL−1). A novel ACE-inhibitory peptide was then isolated from this Mucor-type Douchi using ultrafiltration followed by Sephadex G-25 column chromatography and reverse phase high-performance liquid chromatography. The amino acid sequence of the purified peptide was identified by Edman degradation as His-Leu-Pro (IC50 = 2.37 µmol L−1). The peptide is a competitive inhibitor and maintained its inhibitory activity even after incubation with some gastrointestinal proteases. CONCLUSION: The present study shows that peptides derived from soybean fermentation during Douchi processing could be the main contributor to the ACE-inhibitory activity observed. Copyright © 2009 Society of Chemical Industry
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chemical components of aspergillus type Douchi a chinese traditional fermented soybean product change during the fermentation process
International Journal of Food Science and Technology, 2007Co-Authors: Jianhua Zhang, Eizo Tatsumi, Junfeng FanAbstract:Summary Douchi, a traditional fermented soybean product that originated in China, has been consumed since ancient times as a food seasoning. The influence of fermentation on the chemical components of naturally fermented Douchi and Aspergillus egypticus pure-cultured Douchi was investigated. Changes in per cent and/or concentration of amino-type nitrogen, total acid, reducing sugar, organic acid, amino acids (AA) and isoflavone, along with the neutral protease and β-glucosidase activities during the fermentation, were analysed. The results indicated that fermentation had a significant effect on the concentration of chemical components. The concentration of all free amino acids (FAA) increased gradually during fermentation, to a maximum of 109.54 mg g−1 in 15-day fermented products. The main organic acids in Douchi are 7.788 and 17.778 mg g−1, respectively. During fermentation, the contents of daidzin and genistin decreased from 160.7 and 207.9 to 7.54 and 24.12 μg g−1 respectively. Daidzein and genistein increased from 18.2 and 16.9 to 63.4 and 84.6 μg g−1, respectively.
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Chemical components of Aspergillus‐type Douchi, a Chinese traditional fermented soybean product, change during the fermentation process
International Journal of Food Science & Technology, 2007Co-Authors: Jianhua Zhang, Eizo Tatsumi, Junfeng FanAbstract:Summary Douchi, a traditional fermented soybean product that originated in China, has been consumed since ancient times as a food seasoning. The influence of fermentation on the chemical components of naturally fermented Douchi and Aspergillus egypticus pure-cultured Douchi was investigated. Changes in per cent and/or concentration of amino-type nitrogen, total acid, reducing sugar, organic acid, amino acids (AA) and isoflavone, along with the neutral protease and β-glucosidase activities during the fermentation, were analysed. The results indicated that fermentation had a significant effect on the concentration of chemical components. The concentration of all free amino acids (FAA) increased gradually during fermentation, to a maximum of 109.54 mg g−1 in 15-day fermented products. The main organic acids in Douchi are 7.788 and 17.778 mg g−1, respectively. During fermentation, the contents of daidzin and genistin decreased from 160.7 and 207.9 to 7.54 and 24.12 μg g−1 respectively. Daidzein and genistein increased from 18.2 and 16.9 to 63.4 and 84.6 μg g−1, respectively.
Eizo Tatsumi - One of the best experts on this subject based on the ideXlab platform.
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Isolation and characterisation of a novel angiotensin I-converting enzyme-inhibitory peptide derived from Douchi, a traditional Chinese fermented soybean food
Journal of the Science of Food and Agriculture, 2009Co-Authors: Junfeng Fan, Szesze Tan, Yanyan Zhang, Eizo TatsumiAbstract:BACKGROUND:Douchi, a traditional fermented soybean food, has recently attracted a great deal of attention owing to its superior physiological activity. In the present study the angiotensin I-converting enzyme (ACE)-inhibitory activity of typical Douchi procured from various regions of China was analysed. An ACE-inhibitory peptide derived from the most potent Douchi was also isolated and characterised. The pattern of ACE inhibition and resistance to hydrolysis by gastrointestinal proteases of this peptide are described. RESULTS: ACE-inhibitory activities were detected in all Douchi samples, with IC50 values ranging from 0.204 to 2.011 mg mL−1. Among the Douchi samples, a Mucor-type Douchi exhibited the most potent ACE-inhibitory activity (IC50 = 0.204 mg mL−1). A novel ACE-inhibitory peptide was then isolated from this Mucor-type Douchi using ultrafiltration followed by Sephadex G-25 column chromatography and reverse phase high-performance liquid chromatography. The amino acid sequence of the purified peptide was identified by Edman degradation as His-Leu-Pro (IC50 = 2.37 µmol L−1). The peptide is a competitive inhibitor and maintained its inhibitory activity even after incubation with some gastrointestinal proteases. CONCLUSION: The present study shows that peptides derived from soybean fermentation during Douchi processing could be the main contributor to the ACE-inhibitory activity observed. Copyright © 2009 Society of Chemical Industry
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chemical components of aspergillus type Douchi a chinese traditional fermented soybean product change during the fermentation process
International Journal of Food Science and Technology, 2007Co-Authors: Jianhua Zhang, Eizo Tatsumi, Junfeng FanAbstract:Summary Douchi, a traditional fermented soybean product that originated in China, has been consumed since ancient times as a food seasoning. The influence of fermentation on the chemical components of naturally fermented Douchi and Aspergillus egypticus pure-cultured Douchi was investigated. Changes in per cent and/or concentration of amino-type nitrogen, total acid, reducing sugar, organic acid, amino acids (AA) and isoflavone, along with the neutral protease and β-glucosidase activities during the fermentation, were analysed. The results indicated that fermentation had a significant effect on the concentration of chemical components. The concentration of all free amino acids (FAA) increased gradually during fermentation, to a maximum of 109.54 mg g−1 in 15-day fermented products. The main organic acids in Douchi are 7.788 and 17.778 mg g−1, respectively. During fermentation, the contents of daidzin and genistin decreased from 160.7 and 207.9 to 7.54 and 24.12 μg g−1 respectively. Daidzein and genistein increased from 18.2 and 16.9 to 63.4 and 84.6 μg g−1, respectively.
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Influences of processing and NaCl supplementation on isoflavone contents and composition during Douchi manufacturing
Food Chemistry, 2007Co-Authors: Lijun Wang, Lijun Yin, Masayoshi Saito, Lei Zou, Eizo TatsumiAbstract:Abstract Douchi is popular in China as a fermented soybean food. The effects of NaCl on the isoflavone contents and composition during processing of Douchi, as well as the β-glucosidase activity was investigated. The results indicate that 61% of the isoflavones in raw soybeans were lost when NaCl content was 10%, which is mainly attributed to pre-fermentation (43%) and post-fermentation (18%) during Douchi processing. While a pre-treatment did not generate major differences in total isoflavone content during Douchi processing, isoflavone composition was altered. The levels of aglycones increased, while the corresponding levels of β-glucosides, malonylglucoside and acetylglucoside decreased. Further, isoflavones in the form of aglycones exceeded 90% of total content following post-fermentation. Finally, changes in isoflavone isomer distribution were found to be related to β-glucosidase activity during fermentation, which was affected by NaCl supplementation.
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Chemical components of Aspergillus‐type Douchi, a Chinese traditional fermented soybean product, change during the fermentation process
International Journal of Food Science & Technology, 2007Co-Authors: Jianhua Zhang, Eizo Tatsumi, Junfeng FanAbstract:Summary Douchi, a traditional fermented soybean product that originated in China, has been consumed since ancient times as a food seasoning. The influence of fermentation on the chemical components of naturally fermented Douchi and Aspergillus egypticus pure-cultured Douchi was investigated. Changes in per cent and/or concentration of amino-type nitrogen, total acid, reducing sugar, organic acid, amino acids (AA) and isoflavone, along with the neutral protease and β-glucosidase activities during the fermentation, were analysed. The results indicated that fermentation had a significant effect on the concentration of chemical components. The concentration of all free amino acids (FAA) increased gradually during fermentation, to a maximum of 109.54 mg g−1 in 15-day fermented products. The main organic acids in Douchi are 7.788 and 17.778 mg g−1, respectively. During fermentation, the contents of daidzin and genistin decreased from 160.7 and 207.9 to 7.54 and 24.12 μg g−1 respectively. Daidzein and genistein increased from 18.2 and 16.9 to 63.4 and 84.6 μg g−1, respectively.
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angiotensin i converting enzyme inhibitory peptides in Douchi a chinese traditional fermented soybean product
Food Chemistry, 2006Co-Authors: Jianhua Zhang, Eizo Tatsumi, Changhe Ding, Lite LiAbstract:Douchi, a soybean product originating in China, produces angiotensin I-converting enzyme (ACE) inhibitors with the potential to lower blood pressure. The ACE inhibitory activities of Douchi qu pure-cultured by Aspergillus Egyptiacus for 48 h, and 72 h were compared with Douchi secondary-fermented for 15 d. The results showed that ACE inhibitory activities were improved following the fermentation. ACE inhibitory activities of 48 h-primary-fermented Douchi qu did not change dramatically after preincubation with ACE, but increased greatly after preincubation with gastrointestinal proteases. The results suggest they were pro-drug-type or a mixture of pro-drug-type and inhibitor-type inhibitors. The ACE inhibitors in 48 h-fermented Douchi qu were fractionated into four major peaks by gel filtration chromatography on Sephadex G-25. Peak 2, which had the highest activity, had only one peptide, composed of phenylalanine, isoleucine and glycine with a ratio of 1:2:5.
Guo Yong - One of the best experts on this subject based on the ideXlab platform.
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Digestive properties and antithrombotic effect of fibrinolytic enzyme-rich Douchi vacuum freeze-dried powder
Science and Technology of Food Industry, 2010Co-Authors: Guo YongAbstract:To determine the antithrombotic effect of fibrinolytic enzyme-rich Douchi vacuum freeze-dried powder by oral administration,the enzyme activity of Douchi freeze-dried powder extract was measured to observe the effect of simulated gastric and intestinal fluid on the powder.The dissolution rate on blood clots was measured to observe the antithrombotic effect of the powder in vitro,through which the antithrombotic matter in it was primarily determined.The effect of the powder by continuous intragastric administration on the coagulation system in rats was also evaluated.The results showed that,the powder was greatly affected by simulated gastric fluid,the enzyme activity of which decreased to 56.21%,it was more stable in the simulated intestinal fluid,with remaining enzyme activity more than 82.86%.The dissolution rate of 5% Douchi freeze-dried powder extract on blood clots was 40.84%±3.76%,but it was only 12.48%±2.43% with heated extract.Thrombin time(TT)in rat serum could be prolonged by the powder,but activated partial thromboplastin time(APTT)and prothrombin time(PT)were not affected.In conclusion,the fibrinolytic enzyme-rich Douchi freeze-dried powder was suitable to be made into intestinal dissolving form.In vitro and in vivo antithrombotic effect of the powder was observed,with Douchi fibrinolytic enzyme as primary antithrombotic matter in it.
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In vitro thrombolysis effect and acute toxicity of vacuum freeze-dried powder of fibrinolytic enzyme-rich Douchi.
Modern Food Science and Technology, 2009Co-Authors: Jiang Ceyan, Zhao Shujin, Guo YongAbstract:The in vitro thrombolysis effect of vacuum freeze-dried powder of fibrinolytic enzyme-rich Douchi and its acute toxicity were studied in this paper. The vacuum freeze-dried powder of fibrinolytic enzyme-rich Douchi was made by our laboratory and its dissolution rate on blood clots of rat as well as its acute toxicity was evaluated by maximum dosage method. Results showed that the clot dissolution rates was of 10% and 2.5% when using 59.64%±5.69% and 40.58%±6.37% of fibrinolytic enzyme-rich Douchi extract, respectively. The former, 10% fibrinolytic enzyme-rich Douchi extract, also showed the effect of thrombolysis in vitro. The oral acute toxicity of Douchi vacuum freeze-dried powder of fibrinolytic enzyme-rich to mice was greater than 16 g/kg. So Douchi vacuum freeze-dried powder was non-toxic, with the developing value for further applicaiton.
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Douchi Fibrinolytic Enzyme Production by a Two-phase Solid-State Fermentation
Modern Food Science and Technology, 2008Co-Authors: Guo YongAbstract:Bacillus subtilis DC-12,isolated from Douchi,produces a strong fibrinolytic enzyme with high activity.First Douchi semi-product was made through pre-fermentation by Aspergillus,then solid-state fermentation condition for Douchi fibrinolytic enzyme production by DC-12 using Douchi semi-product as substrate was studied.The results showed that the optimal conditions were as follows:in 250mL Erlenmeyer flask,Douchi semi-product of 35g,glucose of 8.0%,initial moisture content of 1.2 mL.g-1 material,initial pH of 7.0,inoculums size of 12%,incubation temperature of 30℃ and fermentation time of 84 h.Under those conditions,the average fibrinolytic enzyme activity reached 1427 IU·g-1 material,which was 260% than that under un-optimized conditions.
Jianhua Zhang - One of the best experts on this subject based on the ideXlab platform.
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chemical components of aspergillus type Douchi a chinese traditional fermented soybean product change during the fermentation process
International Journal of Food Science and Technology, 2007Co-Authors: Jianhua Zhang, Eizo Tatsumi, Junfeng FanAbstract:Summary Douchi, a traditional fermented soybean product that originated in China, has been consumed since ancient times as a food seasoning. The influence of fermentation on the chemical components of naturally fermented Douchi and Aspergillus egypticus pure-cultured Douchi was investigated. Changes in per cent and/or concentration of amino-type nitrogen, total acid, reducing sugar, organic acid, amino acids (AA) and isoflavone, along with the neutral protease and β-glucosidase activities during the fermentation, were analysed. The results indicated that fermentation had a significant effect on the concentration of chemical components. The concentration of all free amino acids (FAA) increased gradually during fermentation, to a maximum of 109.54 mg g−1 in 15-day fermented products. The main organic acids in Douchi are 7.788 and 17.778 mg g−1, respectively. During fermentation, the contents of daidzin and genistin decreased from 160.7 and 207.9 to 7.54 and 24.12 μg g−1 respectively. Daidzein and genistein increased from 18.2 and 16.9 to 63.4 and 84.6 μg g−1, respectively.
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Chemical components of Aspergillus‐type Douchi, a Chinese traditional fermented soybean product, change during the fermentation process
International Journal of Food Science & Technology, 2007Co-Authors: Jianhua Zhang, Eizo Tatsumi, Junfeng FanAbstract:Summary Douchi, a traditional fermented soybean product that originated in China, has been consumed since ancient times as a food seasoning. The influence of fermentation on the chemical components of naturally fermented Douchi and Aspergillus egypticus pure-cultured Douchi was investigated. Changes in per cent and/or concentration of amino-type nitrogen, total acid, reducing sugar, organic acid, amino acids (AA) and isoflavone, along with the neutral protease and β-glucosidase activities during the fermentation, were analysed. The results indicated that fermentation had a significant effect on the concentration of chemical components. The concentration of all free amino acids (FAA) increased gradually during fermentation, to a maximum of 109.54 mg g−1 in 15-day fermented products. The main organic acids in Douchi are 7.788 and 17.778 mg g−1, respectively. During fermentation, the contents of daidzin and genistin decreased from 160.7 and 207.9 to 7.54 and 24.12 μg g−1 respectively. Daidzein and genistein increased from 18.2 and 16.9 to 63.4 and 84.6 μg g−1, respectively.
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angiotensin i converting enzyme inhibitory peptides in Douchi a chinese traditional fermented soybean product
Food Chemistry, 2006Co-Authors: Jianhua Zhang, Eizo Tatsumi, Changhe Ding, Lite LiAbstract:Douchi, a soybean product originating in China, produces angiotensin I-converting enzyme (ACE) inhibitors with the potential to lower blood pressure. The ACE inhibitory activities of Douchi qu pure-cultured by Aspergillus Egyptiacus for 48 h, and 72 h were compared with Douchi secondary-fermented for 15 d. The results showed that ACE inhibitory activities were improved following the fermentation. ACE inhibitory activities of 48 h-primary-fermented Douchi qu did not change dramatically after preincubation with ACE, but increased greatly after preincubation with gastrointestinal proteases. The results suggest they were pro-drug-type or a mixture of pro-drug-type and inhibitor-type inhibitors. The ACE inhibitors in 48 h-fermented Douchi qu were fractionated into four major peaks by gel filtration chromatography on Sephadex G-25. Peak 2, which had the highest activity, had only one peptide, composed of phenylalanine, isoleucine and glycine with a ratio of 1:2:5.
Zhongmin Zhang - One of the best experts on this subject based on the ideXlab platform.
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Correction: Microbial diversity in two traditional bacterial Douchi from Gansu province in northwest China using Illumina sequencing.
PloS one, 2018Co-Authors: Weibing Zhang, Qiaoqiao Luo, Yan Zhu, Lei Cao, Min Yang, Pencheng Wen, Zhongmin ZhangAbstract:Douchi has been consumed as a flavoring ingredient for centuries. During production of Douchi, numerous microorganisms play important roles in the hydrolysis and conversion of proteins and starch, which are related to the quality and flavor of the end product. Therefore, in the present study, the microbial diversity in two types of home-made traditional bacterial Douchi from Gansu province in northwest China was studied by high-throughput sequencing, and a corresponding analysis of the bacterial and fungal communities were conducted. The results showed that geography may have impacted the fungal diversity and the bacterial and fungal species richness in the samples. The results also showed that the microbial community was significantly different in samples of different origin and the difference in the microbial community at the genus level was greater than at phylum level. Two dominant bacterial genera (Bacillus and Ignatzschineria) were common to the two samples, both of which had a relative abundance of more than 1%. Four bacterial genera (Staphylococcus, Aerococcus, Geobacillus, and Jeotgalicoccus) were dominant only in the sample from Qingyang, while another four (Carnobacterium, Proteus, Aneurinibacillus, and Enterococcus) were dominant only in the sample from Longnan. Two dominant fungal genera (Pichia and Candida) were shared by the two samples. Additionally, two genera (Rhodosporidium and Yarrowia) were dominant only in samples from Longnan. The functional genes of the bacteria present in samples indicated that a significant difference was observed in the bacterial community between samples of different origin. We also found that microbial interactions between bacterial and fungal communities in the samples were very complex. This study provides previously unknown information regarding the impact of the environment on microbial communities in Douchi and lays a foundation for further investigations into food ecology in bacterial Douchi.
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Type of Douchi and soybean, producers and origins of Douchi samples.
2018Co-Authors: Weibing Zhang, Qiaoqiao Luo, Yan Zhu, Lei Cao, Min Yang, Pencheng Wen, Zhongmin ZhangAbstract:Type of Douchi and soybean, producers and origins of Douchi samples.
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Microbial diversity in two traditional bacterial Douchi from Gansu province in northwest China using Illumina sequencing
2018Co-Authors: Weibing Zhang, Qiaoqiao Luo, Yan Zhu, Lei Cao, Min Yang, Pencheng Wen, Zhongmin ZhangAbstract:Douchi has been consumed as a flavoring ingredient for centuries. During production of Douchi, numerous microorganisms play important roles in the hydrolysis and conversion of proteins and starch, which are related to the quality and flavor of the end product. Therefore, in the present study, the microbial diversity in two types of home-made traditional bacterial Douchi from Gansu province in northwest China was studied by high-throughput sequencing, and a corresponding analysis of the bacterial and fungal communities were conducted. The results showed that geography may have impacted the fungal diversity and the bacterial and fungal species richness in the samples. The results also showed that the microbial community was significantly different in samples of different origin and the difference in the microbial community at the genus level was greater than at phylum level. Two dominant bacterial genera (Bacillus and Ignatzschineria) were common to the two samples, both of which had a relative abundance of more than 1%. Four bacterial genera (Staphylococcus, Aerococcus, Geobacillus, and Jeotgalicoccus) were dominant only in the sample from Qingyang, while another four (Carnobacterium, Proteus, Aneurinibacillus, and Enterococcus) were dominant only in the sample from Longnan. Two dominant fungal genera (Pichia and Candida) were shared by the two samples. Additionally, two genera (Rhodosporidium and Yarrowia) were dominant only in samples from Longnan. The functional genes of the bacteria present in samples indicated that a significant difference was observed in the bacterial community between samples of different origin. We also found that microbial interactions between bacterial and fungal communities in the samples were very complex. This study provides previously unknown information regarding the impact of the environment on microbial communities in Douchi and lays a foundation for further investigations into food ecology in bacterial Douchi.